Due to the increased amounts of data being stored and processed today, operational databases are constructed, categorized and formatted in a manner conducive for maximum throughput, access time and storage capacity. Unfortunately, the raw data found in these operational databases often exist as rows and columns of numbers and code that appears bewildering and incomprehensible to business analysts and decision makers. Furthermore, the scope and vastness of the raw data stored in modern databases renders it harder to analyze. As a result, applications have been developed in an effort to help interpret, analyze and compile the data so that it may be readily and easily understood. This is accomplished by mapping, sorting and summarizing the raw data before it is presented for display, allowing individuals to more easily interpret the data and make key decisions based on the collected data.
Extracting raw data from one or more operational databases and transforming it into useful information is the function of data warehouses. In data warehouses, the data is structured to satisfy decision support roles rather than operational needs. Before the data is loaded into the data warehouse, the corresponding source data from an operational database is filtered to remove extraneous and erroneous records, cryptic and conflicting codes are resolved, raw data is translated into meaningful information and summary data that is useful for decision support, trend analysis or other end-user needs is pre-calculated. In the end, the data warehouse is comprised of an analytical database containing data useful for decision support.
In large enterprises, different organizations have, over the years, developed their own data warehouses, often particular to the type of data used by that organization. As a result, the ability to obtain an “enterprise view” of the company's performance is a difficult task, requiring hours of human effort to coordinate and evaluate all of the data from each data warehouse. Additionally, as companies merge and/or acquire other companies, the back-end database systems associated with the merged and/or acquiring entities must be subsumed into the existing systems. This has become a cumbersome activity and an issue that needs to be addressed.